50 research outputs found
Analysis of Collectivism and Egoism Phenomena within the Context of Social Welfare
Comparative benefits provided by the basic social strategies including
collectivism and egoism are investigated within the framework of democratic
decision-making. In particular, we study the mechanism of growing "snowball" of
cooperation.Comment: 12 pages, 5 figures. Translated from Russian. Original Russian Text
published in Problemy Upravleniya, 2008, No. 4, pp. 30-3
Molecular beam epitaxy of high structural quality Bi2Se3 on lattice matched InP(111) substrates
Epitaxial layers of the topological insulator Bi2Se3 have been grown by
molecular beam epitaxy on laterally lattice-matched InP(111)B substrates. High
resolution X-ray diffraction shows a significant improvement of Bi2Se3 crystal
quality compared to layers deposited on other substrates. The measured full
width at half maximum of the rocking curve is Delta omega=13 arcsec, and the
(omega-2theta) scans exhibit clear layer thickness fringes. Atomic force
microscope images show triangular twin domains with sizes increasing with layer
thickness. The structural quality of the domains is confirmed on the
microscopic level by transmission electron microscopy.Comment: 4 pages, 4 figure
Sequential and co-tunneling behavior in the temperature-dependent thermopower of few-electron quantum dots
We have studied the temperature dependent thermopower of gate-defined,
lateral quantum dots in the Coulomb blockade regime using an electron heating
technique. The line shape of the thermopower oscillations depends strongly on
the contributing tunneling processes. Between 1.5 K and 40 mK a crossover from
a pure sawtooth- to an intermitted sawtooth-like line shape is observed. The
latter is attributed to the increasing dominance of cotunneling processes in
the Coulomb blockade regime at low temperatures.Comment: 4 pages, 4 figures, submitted to Phys. Rev.
Very large magnetoresistance in lateral ferromagnetic (Ga,Mn)As wires with nanoconstrictions
We have fabricated (Ga,Mn)As nanostructures in which domain walls can be
pinned by sub-10 nm constrictions. Controlled by shape anisotropy, we can
switch the regions on either side of the constriction to either parallel or
antiparallel magnetization. All samples exhibit a positive magnetoresistance,
consistent with domain-wall trapping. For metallic samples we find a
magnetoresistance up to 8%, which can be understood from spin accumulation. In
samples where, due to depletion at the constriction, a tunnel barrier is
formed, we observe a magnetoresistance of up to 2000 %.Comment: 4 pages, 3 figures, submited to Phys. Rev. Let
A fast and low-power microelectromechanical system-based non-volatile memory device
Several new generation memory devices have been developed to overcome the low performance of conventional silicon-based flash memory. In this study, we demonstrate a novel non-volatile memory design based on the electromechanical motion of a cantilever to provide fast charging and discharging of a floating-gate electrode. The operation is demonstrated by using an electromechanical metal cantilever to charge a floating gate that controls the charge transport through a carbon nanotube field-effect transistor. The set and reset currents are unchanged after more than 11 h constant operation. Over 500 repeated programming and erasing cycles were demonstrated under atmospheric conditions at room temperature without degradation. Multinary bit programming can be achieved by varying the voltage on the cantilever. The operation speed of the device is faster than a conventional flash memory and the power consumption is lower than other memory devices
Multidrug Resistance of <i>F. tularensis</i> subsp. <i>holarctica</i>, Epizootiological and Epidemiological Analysis of the Situation on Tularemia in the Russian Federation in 2022 and Forecast for 2023
The review provides concise information on the innate ability of cells of the tularemia pathogen, Francisella tularensis subsp. Holarctica, to resist antimicrobials through a variety of mechanisms, leading to its multi-resistance. In total, taking into account new territories, 120 cases of human infection were registered in the Russian Federation in 2022. Epizootic manifestations of the infection of varying degrees of intensity were detected in 58 constituent entities. Against this background, sporadic cases of tularemia in humans were reported in 18 regions of the country. An outbreak of tularemia occurred in the Stavropol Territory; the disease of mild and moderate severity was found in 76 people. The increased incidence of tularemia persists in the Republic of Karelia with severe cases of the disease in the absence of immunoprophylaxis of this infection in the region. A total of 61 cultures of the tularemia pathogen F. tularensis subsp. holarctica, out of which 20 erythromycin-resistant strains were isolated in the Stavropol Territory. In addition, 8 cultures of F. tularensis subsp. mediasiatica from a silt sample and mites Dermacentor silvarum and Haemaphysalis concinna caught in the Republic of Altai were isolated. On the territory of the Russian Federation in 2022, 930 999 people were vaccinated and revaccinated against tularemia. Based on the analysis of the data obtained in 2022, epidemic complications in 2023 in the form of sporadic cases of the disease among the unvaccinated population are most likely to occur in the territories of the Central Federal District – in the Vladimir, Ryazan and Smolensk Regions; Northwestern Federal District – in the Arkhangelsk Region and the Republic of Karelia; Southern Federal District – in the Volgograd and Rostov Regions. The situation in the North Caucasian Federal District will remain tense in the Stavropol Territory; in the Volga Federal District – in the territories of the Saratov Region, as well as in the Kirov Region and the Republic of Mordovia; Ural Federal District – in Khanty-Mansi and Yamalo-Nenets Autonomous Districts; Siberian Federal District – in certain territories of Omsk, Kemerovo, Tomsk, Novosibirsk, Irkutsk Regions, Altai, Krasnoyarsk Territories; in the Far Eastern Federal District, the most intense epizootic activity of natural tularemia foci is in Primorsky Krai